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Pacific Southwest, Region 9

Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations

Biological Analysis

The Region 9 Laboratory provides a diverse range of biological laboratory services to support program offices of EPA, states, and tribes in Region 9. The types of assistance available include toxicity testing and microbiological testing. The team also provides analytical support, technical assistance, and training in these three areas. Also find related links to sources of EPA test methods, sediment toxicity, and more.


Aquatic and Sediment Toxicity Testing

Aquatic & Sediment Toxicity Testing Toxicity tests, or bioassays, measure the adverse or toxic effects of samples on a particular organism. Aquatic toxicity tests are laboratory experiments used to assess biological impacts in the environment by exposing aquatic organisms directly to waters or sediments of concern. The Region 9 Laboratory's biology staff conducts a variety of aquatic toxicity tests for programs including:

  • Effluent tests under the National Pollution Discharge Elimination System (NPDES) permits
  • Testing dredged sediment under the Open Ocean Disposal Program
  • Biological monitoring of surface waters
  • Ecological risk assessments at Superfund sites

Region 9 Laboratory's biology staff can conduct acute and short-term chronic toxicity tests with samples such as ambient waters, industrial and municipal effluents, sediment pore waters, sediments, and oil platform drilling muds.

Bluefish Freshwater Toxicity Tests   Freshwater Toxicity Tests - Chronic & Acute

  • Fish - Fathead Minnow (Pimephales promelas) survival and growth
  • Invertebrate - Freshwater cladocera (Ceriodaphnia dubia) survival and reproduction
  • Freshwater cladocera (Daphnia magna) survival, growth, and reproduction
  • Freshwater cladocera (Daphnia pulex) survival
  • Algae - Green microalgae (Selenastrum carpicornutum) growth
  • Amphipod - Hyallela azteca survival in sediments

Fish: Estuarine & Marine Toxicity Tests   Estuarine and Marine Toxicity Tests - Chronic & Acute

  • Echinoderm - Purple sea urchin (Strongylocentrotus purpuratus) fertilization and development
  • Crustacean - Mysid shrimp (Mysidopsis bahia) survival and growth
  • Amphipod - Eohaustorius estuarius survival and reburial in sediments

Toxicity Identification EvaluationsToxicity Identification Evaluations

A Toxicity Identification Evaluation (TIE) is a process of characterizing, identifying, and confirming causative toxicants in a complex effluent waste through a process of chemical/physical manipulations of samples followed by toxicity tests. The Region 9 Laboratory performs acute and chronic Phase I (Toxicity Characterization Procedures) TIEs for freshwater or marine samples.


Microbiological Testing

Microbiological Testing The Region 9 Lab conducts microbiological tests on drinking water, ambient water, wastewater effluent, and groundwater samples to verify the presence or absence of and quantify bacteria indicating fecal contamination.

Microbiological Analyses

Coliforms and E. coli by Colilert, Membrane Filtration, and Multiple Tube Fermentation

  • E. coli
  • Enterococci
  • Heterotrophic Plate Count

Other Biological Analysis   Other Biological Analyses

  • Chlorophyll
  • Biochemical Oxygen Demand

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Technical Assistance

Technical Assistance The Region 9 Laboratory's biology staff are an ongoing resource for technical assistance in biological methods and field sampling techniques, reviews of regional and state projects, and water resources assessment and monitoring programs.

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Links to Related Information

Sources of EPA test methods:

Sediment Toxicity

Whole Effluent Toxicity

Microbiological Methods

Biological Field Methods

Toxicity Identification Evaluations

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